JP2017070744A - Electric vehicle and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric vehicle that is prevented from moving when a user tries to pick up goods or the like with one hand while gripping a handle with the other hand and putting his/her weight on the electric vehicle, and to provide a method of controlling the electric vehicle.SOLUTION: An electric vehicle 10 includes: wheels 13 provided on a frame 11; a brake unit 20 for braking the wheels 13; a pair of handles 14 to be individually operated by a user; and operation sensing means 24 for sensing whether individual ones of the handles 14 are operated by the user. A control unit 16 controls the brake unit 20 on the basis of a signal from the operation sensing means 24. When the user is operating only one of the handles 14, the control unit 16 controls the brake unit 20 to brake the wheels 13.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric vehicle and an electric vehicle control method for assisting walking of an elderly person, a physically handicapped person, an inpatient or other person who has restrictions on walking.

  2. Description of the Related Art Conventionally, walker and other walking assistance devices have been used to assist walking of elderly people who go out (silver cars, wheelbarrows) and physically handicapped or hospitalized patients. For example, Patent Document 1 discloses a walking assist device that can perform straight advancement and turning operations with a simple operation.

  In the walking assistance device (electric wheelbarrow) of Patent Document 1, a frame body having a handle portion gripped by a pedestrian, a plurality of wheels provided on both left and right sides of the frame body, and a plurality of wheels that respectively rotate and drive each wheel. There is disclosed a walking assist device including a drive motor and a control unit that detects a counter electromotive force generated in the drive motor and controls the drive motor based on the counter electromotive force.

  Moreover, in the walking assistance apparatus of patent document 1, the touch sensor which detects whether the pedestrian is grasping the handle part is provided in the handle part. If it is determined that the pedestrian is not grasping the handle based on the detection signal of the touch sensor, control is performed to brake each wheel. However, in this walking assist device, the difference between whether the pedestrian is holding the handle with one hand or the handle with both hands cannot be identified.

JP 2009-183407 A

  By the way, elderly users who use an electric vehicle as a walking assist device, for example, when shopping, leave the weight in the electric vehicle while holding the handle with one hand, and take goods etc. with the other hand. There is a case to try. However, if the brake is not applied sufficiently to the electric vehicle, the electric vehicle may move when the user removes the other hand from the handle while keeping the weight in the electric vehicle. In this case, the user may lose balance and fall.

  The object of the present invention is that the electric vehicle moves even when the user holds the handle with one hand and keeps weight on the electric vehicle while trying to pick up goods etc. with the other hand. It is an object to provide an electric vehicle and a control method thereof.

  An electric vehicle according to the present invention includes a wheel or an endless track provided on a frame, a braking unit that brakes the wheel or the endless track, a pair of handles connected to the frame and operated by a user, An operation detection unit that detects whether or not each of the pair of handles is operated by the user, and a control unit that controls the braking unit based on a signal from the operation detection unit, When the user is operating only one handle of the pair of handles, the braking unit is controlled to brake the wheel or the endless track.

  In the electric vehicle according to the present invention, when the user is stationary and the user operates only the one handle, the control unit controls the braking unit to control the wheel or the wheel. An endless track may be braked.

  In the electric vehicle according to the present invention, when the user is walking and the user is operating only the one handle, the control unit moves the wheel or the endless track by the braking unit. There is no need to brake.

  In the electric vehicle according to the present invention, when the wheel or the endless track is being braked by the braking unit and the user is operating only the one handle, the control unit The wheel or the endless track may be braked by controlling a part.

  In the electric vehicle according to the present invention, the control unit may not brake the wheel or the endless track by the braking unit when the user operates both of the pair of handles.

  In the electric vehicle according to the present invention, the control unit may brake the wheel or the endless track by controlling the braking unit when the user does not operate both of the pair of handles.

  In the electric vehicle according to the present invention, a motor may be connected to the wheel or the endless track, and the motor may serve as both a driving unit and a braking unit that drive the wheel or the endless track.

  In the electric vehicle according to the present invention, when the user does not operate both of the pair of handles and the wheel or the endless track is driven, the wheel or the endless track is The wheel or the endless track may be braked by reversely braking the drive unit that drives the wheel.

  In the electric vehicle according to the present invention, the wheel or the endless track and the drive unit may be provided on each of the left and right sides, and the control unit may control the left and right drive units independently of each other.

  The electric vehicle according to the present invention further includes an inclination detection sensor for detecting the inclination of the vehicle, and the control unit brakes the wheel or the endless track based on the inclination of the vehicle detected by the inclination detection sensor. May be.

  In the electric vehicle according to the present invention, the control unit may change the braking strength of the wheel or the endless track according to the time after the user stops operating both the pair of handles. Good.

  In the electric vehicle according to the present invention, when the user operates one or both of the handles while the driving unit is reversely braked, the control unit may stop reverse braking of the driving unit. Good.

  The electric vehicle according to the present invention further includes an inclination detection sensor for detecting the inclination of the vehicle, and the control unit is configured to detect the inclination of the vehicle when the vehicle is pushed from the outside or when the inclination detection sensor is at a certain inclination of the vehicle. When the vehicle is detected, the wheel or the endless track may be braked by reversely braking the drive unit that drives the wheel or the endless track.

  The electric vehicle according to the present invention further includes an inclination detection sensor for detecting the inclination of the vehicle, and the control unit detects that the vehicle is stationary and the inclination detection sensor detects an inclination of the vehicle above a certain level. If not, the wheels or the endless track may be braked by short-circuiting the phases of the wheels or the drive unit that drives the endless track.

  An electric vehicle control method according to the present invention includes a wheel or an endless track provided on a frame, a braking unit that brakes the wheel or the endless track, and a pair of handles that are connected to the frame and operated by a user. A method of controlling an electric vehicle comprising: determining whether or not the user is operating only one of the pair of handles; and A step of braking the wheel or the endless track when only one of the pair of handles is operated.

  According to the present invention, it is possible to prevent a problem that an electric vehicle moves when a user tries to pick up a product or the like with the other hand while keeping a weight on the electric vehicle while holding a handle with one hand. Can do.

FIG. 1 is a perspective view showing an electrically assisted walking vehicle according to a first embodiment of the present invention. FIG. 2 is a side view showing the electrically assisted walking vehicle according to the first embodiment of the present invention. FIG. 3 is a schematic diagram showing the operation detection means. FIG. 4 is a schematic diagram showing a modification of the operation detection means. FIG. 5 is a flowchart for explaining an example of the operation of the control unit according to the first embodiment of the present invention. FIG. 6 is a table summarizing the conditions when the wheel is braked and when it is not braked in the first embodiment of the present invention. FIG. 7 is a flowchart for explaining an example of the operation of the control unit according to the second embodiment of the present invention.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. In the following description, the same reference numerals are assigned to the same components. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  1 and 2 are views showing an electric walking vehicle (hereinafter referred to as an electric assisting walking vehicle) as an example of an electric vehicle. FIG. 1 is a schematic perspective view showing an example of the appearance of the electrically assisted walking vehicle 10 according to the first embodiment, and FIG. 2 is a side view of the electrically assisted walking vehicle 10 of FIG.

(Configuration of electrically assisted walking vehicle)
As shown in FIGS. 1 and 2, the electrically assisted walking vehicle 10 includes a frame 11, a pair of front wheels 12 and a pair of rear wheels (wheels) 13 provided on the frame 11, and a pair of frames connected to the frame 11. And a handle 14. Each handle 14 is provided with a brake unit 15 for manually stopping the electrically assisted walking vehicle 10.

  The pair of rear wheels 13 is connected to a motor 20 that assists the movement of the corresponding rear wheel 13. A battery 21 and a control unit 16 are attached to the frame 11. Further, the control unit 16 is provided with a speed detection sensor 22. Further, the handle 14 is provided with a gyro sensor (tilt detection sensor) 23 and an operation detection means (grip sensor, operation force sensor) 24, respectively.

  Next, each component of the electrically assisted walking vehicle 10 will be further described.

  The frame 11 includes a pair of left and right pipe frames 31 and a connecting frame 32 that connects the pair of pipe frames 31 in the horizontal direction.

  A pair of front wheels 12 is provided on the front end side of each of the pair of left and right pipe frames 31. The pair of front wheels 12 can be rotated in the front-rear direction, and can also be rotated around the vertical axis.

  A pair of rear wheels 13 is provided on the rear end side of each of the pair of left and right pipe frames 31. Each rear wheel 13 is rotatably provided in the front-rear direction. As a result, the electrically assisted walking vehicle 10 can be easily moved forward and backward, and can be easily moved or changed in the left-right direction.

  A pair of handles 14 are provided at the upper ends of the pair of left and right pipe frames 31, respectively. The pair of handles 14 are each operated by a user. Here, “operated” includes a case where a part of the user's body or his / her belongings leans, is supported, or is in contact with the user's hand. Further, “gripped” means to be held in a wrapping form, and includes not only a case where the object is firmly grasped but also a case where it is grasped lightly. In the present embodiment, a case where a pair of handles 14 are gripped by a user's hand will be described as an example.

  The pair of handles 14 has a rod-like member 41. Each rod-like member 41 is provided with a grip portion 42. In addition, a brake lever 34 is attached to each rod-like member 41. The configuration of the handle 14 is not limited to this, and for example, a bar handle that extends in the horizontal direction is provided so as to connect the pair of left and right pipe frames 31, and the grip portion 42 is provided on the bar handle as the pair of left and right handles 14. You can also.

  The battery 21 supplies power to each element of the electrically assisted walking vehicle 10 such as the motor 20 and the control unit 16. The battery 21 is fixed to a connection frame 32 positioned between the pair of pipe frames 31. Note that an upper portion of the battery 21 is provided with a storage portion 43 that can store a user's luggage. Further, a seating surface 37 on which a user can sit is provided adjacent to the accommodating portion 43.

In the present embodiment, the motor 20 is built in each rear wheel 13.
As the motor 20, an arbitrary motor such as a servo motor, a stepping motor, an AC motor, a DC motor or the like can be used, and a motor in which a speed reducer is integrally formed may be used.

  In the present embodiment, the motor 20 assists the operation of the rear wheel 13 and also has a function as a power generation brake. That is, in the present embodiment, the motor 20 serves both as a drive unit that drives the rear wheel 13 and as a braking unit that brakes the rear wheel 13. When the motor 20 brakes the rear wheel 13, the motor 20 is used as a generator and the resistance force is used as a brake. In addition, when the motor 20 plays a role as a braking unit, as described later, it may be used as a reverse brake for driving the motor 20 in the reverse direction or as a short-circuit brake for short-circuiting the phases of the motor 20. Alternatively, the motor 20 may serve only as a drive unit that drives the rear wheel 13, and the braking unit that brakes the rear wheel 13 may be provided separately from the motor 20. Examples of such a braking unit include an electromagnetic brake and a mechanical brake.

  In the present embodiment, the motor 20 is built in each rear wheel 13. However, the present invention is not limited to this, and the motor 20 may be built only in the pair of front wheels 12. It may be incorporated in all of the front wheel 12 and the pair of rear wheels 13.

  The control unit 16 controls the entire electrically assisted walking vehicle 10 such as the motor 20. In this case, the control unit 16 is provided in the vicinity of the battery 21. Details of the control by the control unit 16 will be described later.

  The speed detection sensor 22 detects the rotation speed or speed of the rear wheel 13 and transmits a signal of the rotation speed or speed to the control unit 16. The speed detection sensor 22 is disposed in the vicinity of the control unit 16. The speed detection sensor 22 may be built in the pair of rear wheels 13 of the electrically assisted walking vehicle 10. Alternatively, like the motor 20, the speed detection sensor 22 may be incorporated only in the pair of front wheels 12 or may be incorporated in all of the pair of front wheels 12 and the pair of rear wheels 13.

  When the motor 20 is a brushless motor, the speed detection sensor 22 may calculate the rotation speed or speed of the wheel and the speed of the electrically assisted walking vehicle 10 using a hall element built in the motor 20. .

  In addition, when speed detection can be performed from the counter electromotive force of the motor 20, the configuration is such that the rotation speed or speed of the wheel and the speed of the electrically assisted walking vehicle 10 are calculated from the counter electromotive force. 13 or the angular velocity of each front wheel 12 can be detected, the rotational speed or speed of the wheel and the speed of the electrically assisted walking vehicle 10 can be calculated from this angular velocity.

  Further, the speed detection sensor 22 is not limited to being built in the pair of front wheels 12 and the pair of rear wheels 13, and may be attached to any other member such as the frame 11, the pair of handles 14, and the like. In this case, when the speed detection sensor is composed of an acceleration detection sensor, the speed is calculated by integrating the acceleration. In addition, when comprised by GPS (global positioning system), it can comprise so that speed may be calculated by differentiating position information.

  The gyro sensor 23 detects the inclination of the electrically assisted walking vehicle 10, for example, whether the electrically assisted walking vehicle 10 is on a flat surface or an inclined surface, and the inclination of the electrically assisted walking vehicle 10 in the front-rear direction or the left-right direction. Is transmitted to the control unit 16. The gyro sensor 23 is provided in the upper part of the electrically assisted walking vehicle 10, for example, inside the pair of handles 14. Alternatively, the gyro sensor 23 may be provided in the vicinity of the control unit 16. The gyro sensor 23 can be provided at the lower part of the electrically assisted walking vehicle 10, but by arranging the gyro sensor 23 at the upper part, the posture of the electrically assisted walking vehicle 10 can be reliably detected as compared with the case where it is disposed at the lower part. Instead of using the gyro sensor, the attitude of the electrically assisted walking vehicle 10 may be detected using an acceleration detection sensor having two or more axes.

  3 and 4 are schematic diagrams for explaining the operation detection means 24. FIG.

  The grip portions 42 of the pair of handles 14 are provided with operation detection means 24 for detecting the force with which the user pushes or pulls the electrically assisted walking vehicle 10 by hand. The operation detection means 24 is regulated by an elastic member (for example, a spring) (not shown) that moves the rod-like member 41 in one or both of the pushing direction and the pulling direction, and further includes a potentiometer for detecting the movement. Is done.

  As described above, the grip portion 42 can move in the front-rear direction with respect to the rod-shaped member 41. When the grip portion 42 moves in the arrow direction (forward direction) in FIGS. Can be determined as being pushed, and when the vehicle moves in the opposite direction (rearward direction) of the arrows in FIGS. 3 and 4, it can be determined that the electrically assisted walking vehicle 10 is being pulled and moves in either direction. If not, it can be determined that none of them is present.

  As a result, whether the user intends to move the electrically assisted walking vehicle 10 forward or whether the user intends to move the electrically assisted walking vehicle 10 backward, the user determines the state of the electrically assisted walking vehicle 10. Can recognize if there is no intention to change.

  The pair of left and right handles 14 are provided with separate operation detection means 24, respectively. Each operation detection unit 24 independently detects the grip force on the handle 14 and transmits the detected grip force to the control unit 16. For this reason, only one of the pair of handles 14 is gripped by the user (one hand holding state), both the pair of handles 14 are not gripped (both hands are released), or the pair of handles 14 are It is possible to recognize whether both are held (both hands are held).

  As shown in FIG. 4, a strain sensor 38 (for example, a strain gauge) is provided in the grip portion 42 so that the moment applied to the grip portion 42 or the pair of pipe frames 31 can be detected. Also good. In this case, since the grip part 42 is fixed with respect to the rod-shaped member 41, a structure becomes simple. Further, a joystick, a push button, or a proximity sensor or pressure sensor for detecting a user's hand may be provided on the grip portion 42, and this may be used as the operation detection means 24.

  In the present embodiment, the control unit 16 controls the motor 20 (braking unit) to control the rear wheel 13 when the user of the electrically assisted walking vehicle 10 is holding only one handle 14 (one-hand holding state). Brake. Specifically, in the control unit 16, only one operation detection unit 24 of the pair of operation detection units 24 detects the grip force on the handle 14, and the other operation detection unit 24 detects the grip force on the handle 14. If not, it is determined that the user is holding only one handle 14 (one-handed state). In this case, the control unit 16 controls the motor (braking unit) 20 to function as a power generation brake, and brakes the rear wheel 13.

  In addition, it is preferable that the control unit 16 brakes the rear wheel 13 when the user is stationary and the user is holding only one handle 14 (in a one-handed state). Specifically, the control unit 16 determines that the speed of the rear wheel 13 detected by the speed detection sensor 22 is a predetermined speed V or less (V is a value of 0 or more) and a pair of operations. When only one of the detection means 24 detects the grip force on the handle 14, the rear wheel 13 is braked. In this case, the control unit 16 determines that the electrically assisted walking vehicle 10 is stopped (or is moving at a low speed) and the user is holding the handle 14 with only one hand, and the electrically assisted walking vehicle It brakes so that 10 may not move. Accordingly, even when the user holds the handle 14 with one hand and leaves the weight to the electrically assisted walking vehicle 10, the electrically assisted walking vehicle 10 can It is possible to prevent a malfunction that moves unexpectedly.

  On the other hand, even when the user is holding only one handle 14 (one-hand holding state), when the user is walking, the control unit 16 is driven by the motor (braking unit) 20. It is preferable not to brake the wheel 13. Specifically, the control unit 16 is a speed at which the speed of the rear wheel 13 detected by the speed detection sensor 22 exceeds a predetermined speed V, and only one operation detection means 24 of the pair of operation detection means 24 is used. When the grip force with respect to the handle 14 is detected, the rear wheel 13 is not braked. In this case, when the user walks while holding the handle 14 with both hands (holding both hands) and temporarily moving only one hand away from the handle 14 (holding one hand), the electrically assisted walking vehicle 10 continues to move without being braked. As a result, even when the user wipes his face with one hand while walking, or when the user suddenly loses power and temporarily moves one hand away from the handle 14, the electrically assisted walking vehicle 10 brakes unnecessarily. It will never be done.

  Even when the user is walking, the rear wheel 13 is being braked by the motor (braking unit) 20 and the user is holding only one handle 14. Therefore, it is preferable that the control unit 16 continues to brake the rear wheel 13. As a result, even if only one handle 14 is pushed while the rear wheel 13 is braked and the rear wheel 13 reaches a speed exceeding the predetermined speed V, the braking of the rear wheel 13 is released. There is no fear of being done.

  As described above, the control unit 16 controls the operation and braking of the motor 20 based on the detection signals of the speed detection sensor 22 and the operation detection unit 24.

(Control method by controller)
Next, a method for controlling the electrically assisted walking vehicle 10 by the control unit 16 will be described. FIG. 5 is a flowchart for explaining an example of the operation of the control unit 16.

  First, the control unit 16 recognizes how the pair of handles 14 are gripped by the user. Specifically, the control unit 16 (1) holds only one of the left and right handles 14 based on the detection signal from the operation detection means 24 provided on each of the pair of left and right handles 14 (one-handed State), (2) a pair of left and right handles 14 are not gripped (both hands are released), or (3) a pair of left and right handles 14 are both gripped (held with both hands). Judgment is made (steps S1 to S3).

  Specifically, when the grip portion 42 of each handle 14 is moved in either the front or rear direction, the operation detection unit 24 detects the grip force with respect to the grip portion 42. In this case, it can be determined that the handle 14 is gripped by the user's hand. On the other hand, when the grip part 42 of each handle 14 is not moved in any direction, the operation detection unit 24 does not detect the grip force with respect to the grip part 42. In this case, it can be determined that the handle 14 is not gripped by the user's hand. By performing this operation for each of the pair of left and right handles 14, the control unit 16 (1) has a one-handed state in which only one of the left and right handles 14 is gripped, and (2) the handle 14 is gripped in both the left and right sides. It can be determined whether the hand is in the released state, or (3) the state in which the handle 14 is held on both the left and right sides.

  Note that the control unit 16 uses the grip force change value (absolute value) in addition to the grip force value (absolute value) to determine whether each handle 14 is gripped by the user's hand. May be determined. In this case, whether or not each handle 14 is gripped can be determined with higher accuracy. For example, when the absolute value of the grip force is less than or equal to a predetermined value and the absolute value of the change in grip force (differential value of the grip force) is less than or equal to a predetermined value, the handle 14 is gripped by the user's hand. Otherwise, it may be determined that the handle 14 is being held by the user's hand. Further, when the grip force and the change in the grip force are within an elliptical area inscribed in a rectangular numerical range defined by each predetermined value, it may be determined that the handle 14 is not gripped by the user's hand. good. In this case, it can be determined with higher accuracy.

  Here, (3) When both of the pair of handles 14 are gripped (when both hands are held), the control unit 16 assists the movement of the rear wheel 13 by the motor 20 without braking the rear wheel 13. (Step S4).

  On the other hand, (2) when both of the pair of handles 14 are not gripped (when both hands are released), the control unit 16 controls the motor 20 (braking unit) to brake the rear wheel 13 (step S5). .

  (1) When only one handle 14 is gripped (in a one-handed state), the control unit 16 determines whether or not the rear wheel 13 is being braked by the motor (braking unit) 20 at that time. (Step S6). If the rear wheel 13 is braked by the motor (braking unit) 20 (Yes in step S6), the control unit 16 continues to control the motor 20 (braking unit) to brake the rear wheel 13.

  On the other hand, when the rear wheel 13 is not braked by the motor (braking unit) 20 (No in step S7), the control unit 16 determines whether the user is stationary or walking (step S7). Step S7).

  Specifically, the speed detection sensor 22 detects the rotational speed or speed of the rear wheel 13 and transmits a signal of the rotational speed or speed to the control unit 16. The control unit 16 calculates the speed of the rear wheel 13 based on the transmitted signal, and compares this speed with a predetermined speed V determined in advance.

  If the rear wheel 13 is moving at a speed higher than the predetermined speed V (No in step S7), the control unit 16 determines that the user is walking, and does not brake the rear wheel 13 without braking the motor. 20 continues to assist the movement of the rear wheel 13 (step S8).

  On the other hand, when the rear wheel 13 is stopped or moving at a predetermined speed V or less (Yes in Step S7), the control unit 16 determines that the user is stationary, and the motor 20 (Brake part) is controlled and the rear wheel 13 is braked (step S9).

  The control unit 16 may determine whether the user is stationary or walking by using the acceleration of the rear wheel 13 in addition to the speed of the rear wheel 13. In this case, it can be determined with higher accuracy whether the user is stationary or walking. For example, when the speed of the rear wheel 13 is equal to or lower than a predetermined speed V and the acceleration of the rear wheel 13 is equal to or lower than the predetermined acceleration, it is determined that the user is stationary and the rear wheel 13 is braked. In other cases, it may be determined that the user is walking and the rear wheel 13 is not braked.

  In addition, the control part 16 repeats the said process until the main power supply of the electrically assisted walking vehicle 10 is turned off.

  Here, FIG. 6 is a table summarizing the conditions when the rear wheel 13 is braked (brake operation) and when the brake is not applied (brake non-operation). As shown in FIG. 6, for example, from a state in which the user grips only one handle 14 while walking (one hand holding state) to a state in which neither of the pair of handles 14 is gripped (both hands are released). When it shifts (arrow A1), the rear wheel 13 is braked and the electrically assisted walking vehicle 10 is stopped. Further, for example, when the user is stationary, the state in which both the pair of handles 14 are not gripped (both hands are released) shifts to the state in which only one handle 14 is gripped (the one-handed state) (arrow A2). ), The state where the rear wheel 13 is continuously braked is maintained.

  As described above, according to the present embodiment, when the user is holding only one handle 14 of the pair of handles 14, the control unit 16 controls the motor (braking unit) 20 to The wheel 13 is braked. Accordingly, even when the user holds the handle 14 with one hand and leaves the weight to the electrically assisted walking vehicle 10, the electrically assisted walking vehicle 10 can It is possible to prevent a malfunction that moves unexpectedly. As a result, the electrically assisted walking vehicle 10 moves while the user leans against the electrically assisted walking vehicle 10, and there is no possibility that the user loses balance and falls.

  Further, according to the present embodiment, the control unit 16 controls the motor (braking unit) 20 when the user is stationary and the user is holding only one handle 14. The rear wheel 13 is braked. Thereby, when a user tries to take goods etc. with the hand which is not grasping the handle 14, the trouble that the electric assist walk vehicle 10 moves unexpectedly can be prevented more effectively.

  Further, according to the present embodiment, when the user is walking and the user is holding only one handle 14, the control unit 16 is controlled by the motor (braking unit) 20 with the rear wheel 13. Do not brake. As a result, even when the user wipes his face with one hand while walking, or when the user suddenly loses power and temporarily moves one hand away from the handle 14, the electrically assisted walking vehicle 10 brakes unnecessarily. Thus, the user can feel secure.

  Further, according to the present embodiment, when the rear wheel 13 is braked by the motor (braking unit) 20 and the user holds only one handle 14, the control unit 16 The motor (braking part) 20 is controlled to brake the rear wheel 13. As a result, even if only one handle 14 is pushed while the rear wheel 13 is braked, and the rear wheel 13 reaches a speed exceeding the predetermined speed V, the braking of the rear wheel 13 is not effective. There is no risk of being released as necessary, and safety can be improved.

  Further, according to the present embodiment, the control unit 16 does not brake the rear wheel 13 by the motor (braking unit) 20 when the user holds both the pair of handles 14. As a result, the stationary user can grip both the pair of handles 14 and start walking smoothly.

  Further, according to the present embodiment, the control unit 16 controls the motor (braking unit) 20 to brake the rear wheel 13 when the user does not hold both the pair of handles 14. Thereby, when a user releases a hand from both of a pair of handles 14 on a slope, for example, there is no possibility that the electrically assisted walking vehicle 10 moves unnecessarily.

  Further, according to the present embodiment, the motor 20 serves as both a drive unit and a braking unit. As a result, it is not necessary to provide a separate braking unit in addition to the motor 20 that assists the movement of the rear wheel 13, and thus the mechanism of the electrically assisted walking vehicle 10 can be simplified.

  In the above-described embodiment, the control unit 16 has been described by taking as an example the case where the pair of rear wheels 13 are braked by controlling the motor (braking unit) 20. Alternatively, the front wheel 12 may be braked. Further, in the present embodiment, the pair of rear wheels (wheels) 13 has been described as an example. However, the present invention is not limited to this, and it is connected to the entire belt so as to surround the starting wheel, the rotating wheel, and the idler wheel (guide wheel). An arbitrary endless track such as a ring of a crawler plate or a caterpillar may be used.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the second embodiment, in addition to the control method according to the first embodiment, the control described below is performed. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

(Configuration of electrically assisted walking vehicle)
In the present embodiment, the motor 20 assists the operation of the rear wheel 13 and also has a function as a reverse brake. That is, in the present embodiment, the motor 20 serves both as a drive unit that drives the rear wheel 13 and as a braking unit (reverse brake) that reversely brakes the rear wheel 13. In other words, when the motor 20 is used as a reverse brake, the motor 20 is reversely rotated with respect to the predetermined rotation direction to give a reverse rotation torque while the motor 20 is rotating in a predetermined rotation direction. Decelerate to brake. In addition, when the motor 20 plays a role as a braking portion, the motor 20 may be used as a generator and used as a power generation brake using the resistance force as a brake. Further, a brake unit such as an electromagnetic brake or a mechanical brake may be further provided separately from the motor 20.

  The left and right motors 20 may be controlled by the control unit 16 as a single unit on the left and right sides, and as will be described later, the left and right motors 20 may be independently controlled. .

  In the present embodiment, the control unit 16 controls the motor 20 when the user of the electrically assisted walking vehicle 10 does not hold both the handles 14 (both hands are released) and the rear wheel 13 is driven. The rear wheel 13 is braked by reverse braking. Specifically, the control unit 16 determines that the user has released his / her hands from both the handles 14 when both of the pair of operation detection means 24 have not detected the grip force with respect to the handles 14. Further, when the speed of the rear wheel 13 detected by the speed detection sensor 22 is equal to or higher than a predetermined speed V (V is a value equal to or higher than 0), the control unit 16 detects that the electrically assisted walking vehicle 10 is on a slope, for example. It is determined that the rear wheel 13 is driving. In this case, the control unit 16 reversely brakes the motor 20 to brake the rear wheel 13 and stop the electrically assisted walking vehicle 10.

  In addition to the above, the control unit 16 may brake the rear wheel 13 based on the inclination of the electrically assisted walking vehicle 10 detected by the gyro sensor 23. That is, when the user of the electrically assisted walking vehicle 10 does not hold both the handles 14, the rear wheel 13 is driven, and the inclination of the electrically assisted walking vehicle 10 is greater than or equal to a certain level, the rear wheel 13 may be braked. In this case, it is possible to more accurately detect that the electrically assisted walking vehicle 10 has unexpectedly moved on a slope, for example.

  When the motor 20 is reversely braked, the control unit 16 may proportionally control the motor 20. That is, the control unit 16 rotates the motor 20 backward when the electrically assisted walking vehicle 10 is moving forward, and rotates the motor 20 forward when the electrically assisted walking vehicle 10 is moving backward. The electrically assisted walking vehicle 10 may be stopped by the control. The method for controlling the motor 20 is not limited to proportional control, and feedback control such as PID control may be used.

  As described above, the control unit 16 controls the operation and braking of the motor 20 based on the detection signals of the speed detection sensor 22 and the operation detection unit 24. As described above, the control unit 16 may control the motor 20 based on the detection signal of the gyro sensor 23 in addition to the speed detection sensor 22 and the operation detection unit 24.

  Further, according to the present embodiment, the motor 20 serves both as a drive unit that drives the rear wheel 13 and as a braking unit (reverse braking) that reversely brakes the rear wheel 13. As a result, it is not necessary to provide a separate braking unit in addition to the motor 20 that assists the movement of the rear wheel 13, and thus the mechanism of the electrically assisted walking vehicle 10 can be simplified.

  In addition, the configuration of the electrically assisted walking vehicle is the same as that of the first embodiment (see FIGS. 1 to 4).

(Control method by controller)
Next, a method for controlling the electrically assisted walking vehicle 10 by the control unit 16 according to the present embodiment will be described. FIG. 7 is a flowchart for explaining an example of the operation of the control unit 16.

  First, similarly to the case of the first embodiment, the control unit 16 recognizes how the pair of handles 14 are gripped by the user. Specifically, the control unit 16 is in a state where both of the pair of left and right handles 14 are not gripped based on the detection signals from the operation detection means 24 provided on the pair of left and right handles 14 (both hands are released). It is determined whether or not there is (step S11).

  Here, when both of the pair of handles 14 are gripped (when both hands are held) (No in Step S11), the control unit 16 does not reversely brake the rear wheel 13 and reverses the rear wheel 13 by the motor 20. Continue assisting the movement. When one of the pair of handles 14 is gripped (in the case of one-hand holding state) (No in step S11), the control unit 16 controls the motor 20 as in the case of the first embodiment. The rear wheel 13 is braked.

  On the other hand, when both of the pair of handles 14 are not gripped (when both hands are released) (Yes in Step S11), the control unit 16 determines whether or not the rear wheel 13 is being driven (Step S11). S12).

  Specifically, the speed detection sensor 22 detects the rotational speed or speed of the rear wheel 13 and transmits a signal of the rotational speed or speed to the control unit 16. The control unit 16 calculates the speed of the rear wheel 13 based on the transmitted signal, and compares this speed with a predetermined speed V determined in advance.

  If the rear wheel 13 is not driven, that is, if the rear wheel 13 is stopped or moving at a predetermined speed V or less (No in step S12), the control unit 16 performs the electric assist walking. The vehicle 10 is determined to be stationary, and the reverse braking of the rear wheel 13 is not performed. In this case, the control unit 16 may brake the rear wheel 13 by using the motor 20 as a power generation brake.

  On the other hand, when the rear wheel 13 is driven, that is, when the rear wheel 13 is moving at a speed exceeding the predetermined speed V (Yes in Step S12), the control unit 16 determines that the electrically assisted walking vehicle 10 is on a slope or the like. The rear wheel 13 is braked by determining that it is moving and by reversely braking the motor 20 (step S13).

  The control unit 16 may determine whether the user is stationary or walking by using the acceleration of the rear wheel 13 in addition to the speed of the rear wheel 13. Thereby, it can be determined with higher accuracy whether or not the electrically assisted walking vehicle 10 is moving. For example, when the speed of the rear wheel 13 is equal to or lower than the predetermined speed V and the acceleration of the rear wheel 13 is equal to or lower than the predetermined acceleration, it is determined that the electrically assisted walking vehicle 10 is stationary and the reverse rotation of the rear wheel 13 is performed. In other cases, the rear wheel 13 may be reversely braked by determining that the electrically assisted walking vehicle 10 is moving without braking.

  In addition, the control part 16 repeats the said process until the main power supply of the electrically assisted walking vehicle 10 is turned off.

  As described above, according to the present embodiment, the control unit 16 reversely brakes the motor 20 when the user does not hold both the pair of handles 14 and the rear wheel 13 is driven. Thus, the rear wheel 13 is braked. Thereby, when the user removes his / her hand from the handle 14 on a slope or the like, the electric assist walking vehicle 10 can be prevented from moving unexpectedly. As a result, for example, it is possible to prevent a problem that the electrically assisted walking vehicle 10 approaches the user on an uphill and gives a sense of fear, or the electrically assisted walking vehicle 10 unexpectedly goes downhill.

(Modification of control method in the present embodiment)
Next, in the present embodiment, various modifications of the control method for controlling the motor 20 by the control unit 16 will be described.

(Modification 1 of control method)
When the user of the electrically assisted walking vehicle 10 does not hold both handles 14 and the rear wheel 13 is driven, the control unit 16 performs proportional control on the left and right motors 20 independently. The motor 20 may be reversely braked.

  In general, due to the effect of the caster angle of the front wheels 12, a rotational force is applied to the electrically assisted walking vehicle 10 so that the descending is forward. That is, when the user releases his hand from the handle 14 on the downhill, even if the electrically assisted walking vehicle 10 is slightly tilted, the direction is naturally straight. On the other hand, when the user lifts his / her hand from the handle 14 on the uphill, if the electric assist walking vehicle 10 tilts even a little, a force is applied to amplify the tilt, and the electric assist walking vehicle 10 turns. There is a risk.

  On the other hand, as described above, the control unit 16 independently controls the left and right motors 20 in proportion to each other, so that even when the user releases his hand from the handle 14 on the uphill, the electric assist The trouble that the walking vehicle 10 turns can be suppressed. That is, when the electrically assisted walking vehicle 10 is turning, the rotation speed of the outer rear wheel 13 is larger than the rotation speed of the inner rear wheel 13. For this reason, it is possible to suppress the turning of the electrically assisted walking vehicle 10 by braking (reversely rotating) the outer rear wheel 13 more strongly than the inner rear wheel 13 by proportional control. Thereby, the electrically assisted walking vehicle 10 can be stably stopped even on an uphill.

(Modification 2 of the control method)
When the user of the electrically assisted walking vehicle 10 does not hold both the handles 14 and the rear wheel 13 is driven, the control unit 16 detects the inclination of the electrically assisted walking vehicle 10 detected by the gyro sensor 23. Based on the above, the motor 20 may be reversely braked by proportionally controlling the motor 20. Specifically, the control unit 16 may change the proportional gain of the proportional control according to the inclination of the electrically assisted walking vehicle 10.

  In general, the force for moving the electrically assisted walking vehicle 10 along the inclination direction or the force for turning the electrically assisted walking vehicle 10 is a function of the inclination angle. For this reason, the proportional gain can be set to an appropriate value by using the proportional gain of the proportional control as a function of the angle of inclination. By preventing the proportional gain of the proportional control from becoming too small, it is possible to prevent problems that the electrically assisted walking vehicle 10 cannot be completely stopped or that it takes time to decelerate the electrically assisted walking vehicle 10. be able to. Further, it is possible to prevent the electrically assisted walking vehicle 10 from turning on an uphill. On the other hand, by preventing the proportional gain of the proportional control from becoming too large, the problem that the proportional control diverges and the electrically assisted walking vehicle 10 causes a pendulum motion can be prevented.

(Modification 3 of the control method)
When the user of the electrically assisted walking vehicle 10 does not hold both the handles 14 and the rear wheel 13 is driven, the control unit 16 is configured so that the user can no longer hold both the handles 14. Depending on the time, the proportional control method of the motor 20 may be changed, whereby the strength of braking of the rear wheel 13 may be changed. Specifically, the control unit 16 relatively reduces the proportional gain immediately after the user no longer holds both the handles 14, and the proportional gain increases as time elapses after the user stops holding the handle 14. You may make it enlarge. In this case, immediately after the user stops gripping both handles 14, the rear wheel 13 is weakly braked, and as the time elapses after the handle 14 is no longer gripped, the rear wheel 13 is strongly braked.

  Thus, by reducing the proportional gain immediately after the user lifts his hands from both handles 14 and braking the rear wheel 13 weakly, the movement of the electrically assisted walking vehicle 10 becomes too steep, and the user is injured. It is possible to prevent a problem that a feeling of fear is given or the proportional control diverges and the electric assist walking vehicle 10 causes a pendulum motion. Further, when the user releases his hand from the handle 14 in a state where the electric assist walking vehicle 10 is tilted, it is possible to prevent a problem that the right and left rear wheels 13 are too different from being able to perform control properly. As described above, the proportional gain immediately after the user releases the hands from both the handles 14 is reduced, and the proportional gain is increased with the time the hands are released from the handle 14 to thereby vibrate the electrically assisted walking vehicle 10. It is possible to calmly stop without causing it.

(Modification 4 of control method)
The control unit 16 may stop the reverse braking of the motor 20 when the user grips one or both of the handles 14 while the motor 20 is reversely braked by the proportional control. In particular, when the user grips only one handle 14, the control unit 16 may stop the reverse braking of the motor 20 and brake the rear wheel 13 by using the motor 20 as a power generation brake.

  Thereby, when the user holds the handle 14 while proportionally controlling the motor 20, the vibration of the control is transmitted to the user's hand, and the user can be prevented from feeling uncomfortable. Further, the force that pushes or pulls the handle 14 affects the movement of the electrically assisted walking vehicle 10, and it is possible to prevent a problem that an unexpected force is generated and control is diverged.

(Modification 5 of the control method)
When it is necessary to brake the rear wheel 13 by the motor 20, for example, in the case of “brake operation” shown in FIG. 6, the control unit 16 may further perform the following determination to perform the brake control of the motor 20. . That is, the control unit 16 determines whether to use the motor 20 as a reverse brake or a short-circuit brake based on the following conditions. In this case, the motor 20 is used not only as a reverse brake that drives the motor 20 in the reverse direction but also as a short-circuit brake that short-circuits the phases of the motor 20.

  Specifically, the control unit 16 controls the motor 20 when the electrically assisted walking vehicle 10 is pushed from the outside or when the gyro sensor 23 detects a certain inclination of the electrically assisted walking vehicle 10. The rear wheel 13 may be braked by reverse braking. Here, “when the electrically assisted walking vehicle 10 is pushed from the outside” means, for example, (1) whether the rear wheel 13 is rotating or (2) a grip force (operating force) with respect to the handle 14 is a certain level or more. (3) You may judge by those combinations. Further, the “tilt of the electrically assisted walking vehicle 10” can be determined by the gyro sensor 23 detecting that the electrically assisted walking vehicle 10 is inclined more than a certain amount in the front-rear or left-right direction.

  On the other hand, when the electrically assisted walking vehicle 10 is stationary and the gyro sensor 23 does not detect a certain inclination of the electrically assisted walking vehicle 10, the control unit 16 short-circuits the phases of the motor 20. The rear wheel 13 may be braked by short-circuit braking 20. Here, whether or not the electrically assisted walking vehicle 10 is stationary can be determined based on the speed of the rear wheel 13 detected by the speed detection sensor 22. Further, the “tilt of the electrically assisted walking vehicle 10” can be determined by the gyro sensor 23 detecting that the electrically assisted walking vehicle 10 is inclined more than a certain amount in the front-rear or left-right direction.

  It should be noted that the motor 20 may be switched from the state where the reverse braking or the short braking is already performed to the short braking or the reverse braking based on the above conditions.

  In general, when the electrically assisted walking vehicle 10 is stopped, it is preferable to use short-circuit braking rather than reverse braking because the battery consumption is low and the quietness is high. On the other hand, when the electrically assisted walking vehicle 10 cannot be completely stopped by short-circuit braking, it is preferable to use reverse braking. Specifically, when the electrically assisted walking vehicle 10 is pushed by an external force (for example, the user is leaning with one hand), the rear wheel 13 rotates in the direction pushed by the user. It is preferable to stop the electrically assisted walking vehicle 10 using reverse braking. Further, when the electrically assisted walking vehicle 10 is stopped on an inclined surface, even if the rear wheel 13 stops rotating and is switched to short-circuit braking, the rear wheel 13 starts to move immediately. For this reason, it is preferable to use reverse braking also when the electrically assisted walking vehicle 10 is stopped on an inclined surface. In addition, since the rear wheel 13 will rotate also when the electrically assisted walking vehicle 10 stops on the inclined surface inclined left and right, it is preferable to use reverse braking.

(Modified example of components of electric assist walking vehicle)
Next, modified examples of the components of the electrically assisted walking vehicle 10 will be described. In the present embodiment, the control unit 16 has been described by taking as an example the case where the pair of rear wheels 13 is braked by reversely controlling the motor 20, but the present invention is not limited to this, and the rear wheels 13 and / or the front wheels 12 are controlled. Reverse braking may be used. Further, in the present embodiment, the pair of rear wheels (wheels) 13 has been described as an example. However, the present invention is not limited to this, and it is connected to the entire belt so as to surround the starting wheel, the rotating wheel, and the idler wheel (guide wheel). An arbitrary endless track such as a ring of a crawler plate or a caterpillar may be used.

  Each embodiment of the present invention has been described above. However, each of the above embodiments is presented as an example, and is not intended to limit the scope of the invention. Each of the above embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. Each of the above embodiments and modifications thereof are included in the scope of the invention and the gist thereof, and are also included in the invention described in the claims and the equivalent scope thereof.

DESCRIPTION OF SYMBOLS 10 Electric assist walk vehicle 11 Frame 12 Front wheel 13 Rear wheel 14 Handle 15 Brake unit 16 Control part 20 Motor 21 Battery 22 Speed detection sensor 23 Gyro sensor 24 Operation detection means

Claims (15)

Wheels or endless tracks provided on the frame;
A braking unit for braking the wheel or the endless track;
A pair of handles connected to the frame, each operated by a user;
Operation detecting means for detecting whether or not each of the pair of handles is operated by the user;
A control unit for controlling the braking unit based on a signal from the operation detection means,
The control unit controls the braking unit to brake the wheel or the endless track when the user operates only one handle of the pair of handles.   When the user is stationary and the user is operating only the one handle, the control unit controls the braking unit to brake the wheel or the endless track. The electric vehicle according to claim 1, wherein:   When the user is walking and the user is operating only the one handle, the control unit does not brake the wheel or the endless track by the braking unit. The electric vehicle according to claim 1 or 2.   When the wheel or the endless track is being braked by the braking unit and the user is operating only the one handle, the control unit controls the braking unit to control the wheel. Or the said endless track is braked, The electric vehicle as described in any one of Claim 1 thru | or 3 characterized by the above-mentioned.   5. The control unit according to claim 1, wherein when the user operates both of the pair of handles, the braking unit does not brake the wheel or the endless track. 6. The electric vehicle as described in.   6. The control unit according to claim 1, wherein the control unit controls the braking unit to brake the wheel or the endless track when the user does not operate both of the pair of handles. The electric vehicle according to claim 1.   7. The motor according to claim 1, wherein a motor is connected to the wheel or the endless track, and the motor serves as both a drive unit and a braking unit that drive the wheel or the endless track. The electric vehicle according to one item.   The control unit reverses the drive unit that drives the wheel or the endless track when the user does not operate both of the pair of handles and the wheel or the endless track is driven. The electric vehicle according to claim 1, wherein the wheel or the endless track is braked by braking.   The electric vehicle according to claim 8, wherein the wheel or the endless track and the drive unit are provided on each of the left and right sides, and the control unit controls the left and right drive units independently of each other.   The vehicle further comprises an inclination detection sensor that detects the inclination of the vehicle, and the control unit brakes the wheel or the endless track based on the inclination of the vehicle detected by the inclination detection sensor. The electric vehicle according to 8 or 9.   The control unit changes a braking strength of the wheel or the endless track according to a time after the user stops operating both of the pair of handles. The electric vehicle according to any one of 10.   9. The control unit according to claim 8, wherein when the user operates one or both of the handles while reversely braking the drive unit, the control unit stops reverse braking of the drive unit. The electric vehicle according to any one of 11.   An inclination detection sensor for detecting the inclination of the vehicle is further provided, and the control unit is configured to detect when the vehicle is pushed from the outside, or when the inclination detection sensor detects a certain inclination of the vehicle. The electric vehicle according to claim 1, wherein the wheel or the endless track is braked by reversely braking a drive unit that drives the wheel or the endless track.   An inclination detection sensor for detecting the inclination of the vehicle; and the control unit includes the wheel when the vehicle is stationary and the inclination detection sensor does not detect a certain inclination of the vehicle. The electric vehicle according to claim 1, wherein the wheel or the endless track is braked by short-circuiting phases of driving units that drive the endless track. Controlling an electric vehicle having wheels or an endless track provided on a frame, a braking unit for braking the wheel or the endless track, and a pair of handles connected to the frame and operated by a user, An electric vehicle control method comprising:
Determining whether the user is operating only one of the pair of handles;
And a step of braking the wheels or the endless track when the user is operating only one of the pair of handles.

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